HISTORY AND ANATOMY OF THE GOLDFISH 



capacious and opens into a well-defined stomach furnished with a valve, 

 behind which are a number of enlargements or appendages, the pyloric 

 caeca, which probably serve as the pancreas. The intestinal canal is a con- 

 voluted tube lined by a mucus membrane which winds in easy turns from 



FIG. 4 — Interior anatomy of the Goldfish, showing parts referred to in descriptions. 



1 Gullet and gills. 5 Vertebra. 9 Kidney. 



2 Eye socket. 6 Heart. 10 Milt. 



3 Nasal passage. 7 Swimming-bladder. 1 1 Intestines. 



4 Brain. 8 Liver. 8a Stomach. 12 Anus. 



the pylorus to the anus. The liver is large, the gall-bladder distinct, and 

 the kidneys, situated outside of the peritoneal cavity, form two elongated 

 organs below the spine. 



The swimming bladder is large and consists of a constricted sac di- 

 vided into an anterior and a posterior portion which contains air. It is 

 placed above the alimentary canal and communicates with the gullet by a 

 duct. It serves to maintain the specific gravity and to change the centre 

 of gravity of the fish and is enlarged or contracted by muscular action, 

 whereby the air is expanded or compressed. When this bladder is rup- 

 tured, malformed or diseased the fish loses all power of changing its posi- 

 tion except in limited motion over the bottom of the tank, or is helpless 

 on the surface of the water. 



The reproductive system of the goldfish is oviparous, the ovaries of 

 the female being known as the roe and the testes of the male as the milt. 

 The ovaries are placed below the spinal column on each side of the swim- 

 ming bladder and posteriorly united with a Fallopian tube or oviduct which 

 leads to an opening behind the anus. The milt of the male are similarly 

 located, and contain a thick white fluid in which are the spermatozoa. The 

 eggs or spawn when laid, are slightly compressed globules, about the size 

 of the head of a pin, of semi-transparent, white or yellowish color. Fecunda- 



